超声冲击对厚板异种钢T型焊接接头组织与硬度的影响  

Effect of Ultrasonic Impact on Microstructure and Hardness of Thick Plate Dissimilar Steel T-type Welded Joints

作　　者：汪子钊 张俊 孙高辉 全顺红 刘华兵 甘进[1] 吴卫国[1,3] 汪舟[4] WANG Zizhao;ZHANG Jun;SUN Gaohui;QUAN Shunhong;LIU Huabing;GAN Jin;WU Weiguo;WANG Zhou(School of Naval Architecture,Ocean and Energy Power Engineering,Wuhan University of Technology,Wuhan 430063,China;China Railway Heavy Machinery Co.,Ltd.,Wuhan 430063,China;Green&Smart River-Sea-Going Ship,Cruise and Yacht Research Center,Wuhan University of Technology,Wuhan 430063,China;School of Automotive Engineering,Wuhan University of Technology,Wuhan 430063,China)

机构地区：[1]武汉理工大学船海与能源动力工程学院,武汉430063 [2]中铁重工有限公司,武汉430063 [3]武汉理工大学绿色智能江海直达船舶与邮轮游艇研究中心,武汉430063 [4]武汉理工大学汽车工程学院,武汉430063

出　　处：《机械工程材料》2023年第11期6-11,共6页Materials For Mechanical Engineering

基　　金：国家自然科学基金面上资助项目(51879208);湖北省自然科学基金青年项目(20231j0222)。

摘　　要：在18,27μm冲击振幅下对Q420qD/20MnMoNb厚板异种钢T型焊接接头焊趾区进行超声冲击处理,分析了不同冲击振幅下焊趾处的显微组织、残余应力以及显微硬度,并与超声冲击前的进行了对比。结果表明:超声冲击处理后焊趾表层出现塑性变形层、大量位错及较高残余压应力,晶粒细化,硬度提高。当超声冲击振幅由18μm增至27μm,塑性变形层深度由约120μm增大至144μm,亚晶尺寸进一步细化至约25 nm,位错密度进一步增大至约2.48×10^(14)m^(-2);表面残余压应力增大至约433 MPa,其影响深度增大至约1410μm;表面硬度增大至约400 HV,硬化层深度增加至约900μm。Ultrasonic impact was conducted on the weld toe region of Q420qD/20MnMoNb thick plate dissimilar steel T-type welded joints with 18,27μm impact amplitudes,and the microstructure,residual stress and microhardness at the weld toe were analyzed under different impact amplitudes,and compared with those before ultrasonic impact.The results show that after ultrasonic impact,a plastic deformation layer,a lot of dislocations and a high compressive stress appeared on the surface layer of the weld toe,the grains were refined,and the hardness increased.When the ultrasonic impact amplitude increased from 18μm to 27μm,the depth of the plastic deformation layer increased from about 120μm to 144μm,the subcrystalline was further refined to about 25 nm in size,and the dislocation density increased to about 2.48×10^(14) m^(-2);the residual compressive stress on the surface increased to about 433 MPa and its affected depth increased to about 1410μm;the surface hardness increased to about 400 HV and the depth of hardening layer increased to about 900μm.

关 键 词：超声冲击 厚板T型焊接接头 显微组织 残余应力 硬度 

分 类 号：TG176[金属学及工艺—金属表面处理]